Friction and heat resisting article and method for manufacturing the same



M May13, 1930. W. NANFELDT .1,758,055

FRCTION AND HEAT RESISTING ARTICLE AND METHOD FOR MANUFACTURING THE SAMEFiled Nov. 6, 1925 ll. @ha -Z''f' E llllllllll Patented May 1.3, 1930 y'uNirED STATES PATENT OFFICE i A 4 l WILLIAM NANFELDT, OF HAVEN,CONNECTICUT, ASSIGNOR TO WORLD BESTOS CORPORATION, OF YORK, N. Y., A.CORPORATION OF DELAWARE i v raicrIoN AND 4 applic-.ationl ledNovember 6,1,925. Serial No. 67,399.

This'invention relates to the manufacture of friction and heat resistingarticles, and

. more particu1arly,.to the manufacture of yarn from material such asasbestos, to paper of such material, to the manufacture of said paperfrom such material, to'yarn made from such material, to a method ofmaking the yarn, to apparatus for making suoli yarn, and

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to fabrics made from such yarn.

More specifically, the invention relates to the manufacture of yarnadapted for different uses but having characteristic advantages for usein friction fabrics suitable for brake and transmissionlinings. p

Heretofore, it has been proposed to make paper from asbestos materialand after forming the same into rolls, to form the material of suchrolls into flat rolls of strip material.v Then each strip, usually in.moistened condition, is drawn preferably from the center of the flatrollunder low tension and twisted with one' or more supporting orreinforcing filaments, combined with the strip one att a time or morethan one at a time. There may also be a plurality of successive twistingoperations. l

The strip material, so far as the herein described method of andapparatus for making yarn visfconcerned, may be formed as described inthe co-pendingapplication of J. A. Heany, Serial No. 516,12),filedNovember 18, 1921. The asbestos material is formed into a pulp vandpassed through an ordinary paper making machine to form a web, which isrolled up in theusual manner. This web, which in the paper makingoperation has been rendered sufficiently strong to permit slitting, isslitted by a slitting machine into narrow strips to bev4 utilized inyarn manufacture. It should be understood that in thenishing of the web,

the material of the surfaces thereof has been with the asbestos materialin the pulp, suitstrengthened, and that the strength of the finished webis to a large extent dependent upon the strength of the surface portionsthereof. Satisfactory results in the manufacture of the web are obtainedby combining able binding material, which serves to increase thestrength or coherence of the iinished yarn or paper, thus rendering itsuitable for manipulation in the' yarn making operan HEAT. REsIs'riNGARTICLE 'AND METHOD' Fon MANUFACTURING TEE SAME A Other objects of theinvention are to pro vide paper strip material containing a binder whichwill retain its strength when wet;

paper strip material which has friction mag terial disseminatedtherethrough; paper strip material containing a binder includingfriction material; paper strip materialA containing a binder throughwhich is disseminated material adapted to prevent undue hardening of thebinder; paper strip material containing a binder through which isdisseminated material adapted to provide for a relatively smoothfriction effect; an advantageous method of making suchvpaper; anadvantageous method of making such improved yarn; and improvedyarn-making mechanism.

Various other-ob]ects of the invention relate to the manufacture of theasbestos paper,

to yarn structure having particular utility for friction fabrics andadapted to withstand wearin the presenceof heat and oil, and toconsiderations relating to details ofthe process, apparatus and product,such as will appear upon reference to the detailed description below andto thel accompanying drawings, in which Figure l-is'a view of theinechanismvfor sol supporting and feeding the yarn composing elements tothe twisting mechanism; Figure 2 is a view of the apparatus employed inthe second step of the process of making the yarn;

Figure 3. is a view of the apparatus einployed in the third step of theprocess of making yarn;

` Figure 4 is a view of a short length of the completed yarn;

Figure 5 is a section of the yarn shown in Figure 4;

Figure 6 is a plan of fabric made from such yarn; and

Figure is a section of the fabric of Figure 6.

In the process of the present invention, there is manufactured asbestospaper formed of asbestos material containing asbestos tibres of anyavailable or suitable length, held together by binding material of sucha nature as to retain its strength under all Working conditions as, forexample, When the pa-l per is- Wet." Heretofore, asbestos paper for thispurpose has been held together, to a great extent, by binding materialwhich is generally Water soluble, or material which may be -softened byWater and which by use of a sufficient amount of Water may bebroughtinto colloidal suspension. As a result of the low tensilestrength of such asbestos paper When Wet, considerable difficulty hasbeen met in so handling it as to withstand the strain of the mechanicalvvorking necessary in yarn manufacture. Such difiiculties have beenovercome to aA great `extent by the use of another kind 'of binding material.

One binder which gives the proper result contains rosin which isintroduced in a suitable manner. Ordinary rosin dissolved in solvents,such as gasoline, alcohol and other hydrocarbons, would not answer, forthe reason that when such a binder is placed in a beater with asbestos,Water and other binders, which are soluble or capable of being broughtinto colloidal suspension, (starch for example) the rosin would give upits solvent and Would be precipitated in the bottom of the beater. A'binder which is free from lthese defects has been obtained by a methodwhich will noWI be described.

Preferably the method is-put into practice in the following manner.Caustic soda is added to starch in a suitable container and treated Withsteam (boiled). Then alum is added, and after mixing, the mixture ispoured into a beater which has previously been charged with asbestos.material and Water. The beater roll is then lowered and the beaterstarted. Then a new mixture of starch and caustic soda is made, andsodium rcsinate (rosin soap) treated With hot Water is added and theingredients thoroughly mixed. Then a few minutes before starting theformation of paper, the last mixture is added to the beater.

` stood that the alum acts to render the rosin It should be underconsiderable tension -and the strain of ine-- chanical Working duringthe process of manufacturing yarn.

One of the more important features of my invention is to add materialwhich tends to prevent the binder from becoming too hard and stili', andalso to render the frictional effect thereof comparatively smooth anduniform. Preferably, use is made for this purposeof graphitesubstantially free'from impurities, such as silica and mica. Graphite ofthe quality used in manufacturing leads for lead pencils, may beutilized. Preferably, the graphite is placed in the beater at any timebefore the addition of the sodium resinate, and by the action of thebeater, is disseminated thoroughly through the pulp. The resulting paperWill then have the resin and graphite distribute therethrough to asuflicient degree of uniformity. It should be understood that thegraphite may be of value in connection with binders other than rosinbinders.

y T he manufacture of the paper may be performed by the use of anapparatus such as shown in the application of J. A. Heany, Serial No..692,947, filed: February 15, 1924, now Patent No. 1,642,495, grantedSeptember 13, 1927. After the paper has been made and Wound into rolls,the material of these rolls may be cut into strips which are normallyformed into flat rolls of such asbestos strip material.

Before making these strips or bands into yarn, the material of thestrips is preferably softened and rendered more flexible, as bynioistening. Preferably this is done by dip ping the rolls into a tankcontaining Water,

for a short interval of time which has been the strips in 'the water ofthe aforesaid tank,

the proportion of glycerine in the solution being about 10% by volume.

Glycerine has the properties of dissolving without limit in water and ofabsorbing as much as 50% of Water from the air, and on account of itsnever drying quality is useful to keep the paper strips moist andsupple. The paper contains considerable starch and this is kept soft bythe glycerine.

Referring to Figure 1 of the drawing, I

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paper and permit easier working of the strip 'i have shown apparatussimilar to that dis closed in m copending application, Serial N o.28,777 led: April 17, 1925, now Patent No. 1,585,628, granted May 18,1926, which is here used for supporting spools of material such ascotton thread and moistened rolls of asbestos strip material, unitingthe threads" and strip material at a predetermined point, and guidingthe united elements-into a twisting device 1.- Fixed to ,a plurality ofstandards, one of which is shown at 2, are a plurality of cross beams orbars 8, 4, 5 and 6; from which the various spools and guides aresupported. Projecting perpendicularly from the inclined front face ofthe beam 8 are pins`7 and 8 on which are placed spools 10 and 11which'carry, respectively, cotton cords or threads y12 and 18, which maybe of either right or left twist according to requirements. The cottonthreadv12 passes through a guide A14 to the upper end of a clamping ortension device 15 which serves to retard the'move- Vment of the threadand exert a suii'icient degree of tension thereon to maintain the samefree of knots or undesirable twists. This clamping or tension device maybe substantially the same as described in my said application, Serial`No.. 28,777, Patent No. 1,585,626. Below the tensiondevice 15 thestrand'12 is led through a circular guide 16 of suitable material, such asporcelain, supported from Athe beam 5,v and is combined at -this pointwith `an asbestos strip 17 and then passed friction cylinder18.supported by the beam as to permit feeding of the strip from the`center of theroll' to and through three guides 22, 28 and 28', in theorder mentioned.

Theintcrmediate guide 28 is mounted on the lower end of an arm 24pivoted,l asshown in-I my said copending` application, to the beam 5,thus permitting the guide 28 to be shifted toand from the line throughthe otherguides to vary the tension of the strip. IThe strip 17 isneedled through these guides or, if the strip is mechanically weak,through two or only one-of these guides and thence into the mainV axialguide or cylinder 16 into union with the-filament or core. Tray-21 maybe preferably provided with an u )standing riin25 to prevent the iiowthere romv of the water used to moisten the paper of the asbestos rollsto modify the binder in the during the twisting operations. i

The second cotton cord 18 is led from the Aspool `twister -1.- From vaneye 29 cord 2 and the asbestos 6 where it is `combined with the cottonstrand 18 and is fed into the twister 11 adjacent to spool 10 throughatension device `26, the strand being guided at the top of the tensiondevice by a guide 27 and at the bottom of the tension-*device by a guide28, which is necessary to maintain the cord 18 'in its proper directionthroughthe tensiondevic'e 26 and to prevent the cord from being drawn toone side by the ini' clined stretch thereof extendingtoward the i theguide 28, the cord 18 passes iii an inclined direction to and through onthe end of a'n arm'80 fixed to the beam 6, and from the eye 29 thefilament passes into the combined with the strand 81 formed of the paperstrip 17. From'the friction cylinder 18the strand 81 and the cord 18 arepassed downwardly through a central sleeve 82 of the twister,

,having thereon a pulley 88 near its upper end,

and at its lower end a member 84 perpcndicular thereto. From the sleeve82 the yarn is ,passed around a pulley 84T on .the member 84,' and thenwound back and forth around shafts and 86 journaled in the cross mem.

ber 84. Surrounding the twisting sleeve 82 is a winding sleeve-87carrying at its upper frictioncylinder 18 where it is end a pulley 88and at its lower end a gear 89,

sleeve. 87`beiiig supported in a bracket 4G.

rlhe gear 89 at the lower end of the sleeve 87, engages gears 41 and 42at the upper ends, respectively, of said shafts 85 and 86, each of whichis provided with three discs 42 to guide the strand or yarn 48 so thatit will be fed around the shafts 85 and 86 and through. an eye 44downwardly to an eye 45/in a fiyer arm 46, another flyer arm 47 beingshown at the opposite end of the cross member 47 at of said shafts 85and 86@` From the the ends loop or eye 45 the preliminary yarn or strand48 passes to a spool 49,'loosely mounted on a vertical shaft 50 which,ports the member 47, and at its lower end, is supported by a bearing 51.'s

It will be seen tlhat upon driving the pul-.

leys 88 and`88 by belts 52 and 58, respectively, the member` 84 will beturned and the strand 81 twisted. This movement of the member 84, inconnection with the driving of' the sleeve 87 from the pulley 88willcause the gears 41 'ande 42to be driven by the gearv89 to turn theshafts 88 and 84 and draw the strand 48 around the at its upper end,suppulley 84 and around shafts 85Av and 86, and will also cause thestrand to pass through the guides 44 and 45 and be wound on the spool49, which is moved y up and down during such winding by means o/f aheart-shaped cani 54 'acting on roll 55 on l'one end of a lever 56pivoted at 57, and having -at its other end a roll 58 o n which thespool rests.

and 18 are of two or more plies. The thread 12 and the strip 17 aretwisted together to the Preferablythe cotton threads or cords 12' fromthe pa )er and lauses irregularities in' the .strands or yarns.According to the present invention, the cotton threads are treated withsuitable material, preferably light paraffin or evlinder oil. towater-proof the threads and thereby avoid disadvantageous effects suchas shrinkage.

In the second operation, the spool 49 containing the strand i3,resulting from the first operation,'is removed from the spindle 50 afterlifting the latter out of its bearing 5l -and placed on an inclined pin61 projecting from a beam, corresponding to the upper beam 3 of theframe shown in Figure 1. and the strand 13 is passed downwardly from thespool through aguide (32 just above atension device (S3. correspondingto tension de- Vices 15 and QG, shown in Figure 1. From the tensiondevice, the strand 43 passes downwardly to a point where it isdeliected, to some extent.` by means including a tension rod G5 mountedon a beam corresponding to the beam 6. At its free end the tension rod65 is provided with an open eye 6G through which the strand :tfpassesand beneath which it is united with one or more filaments. such as wires($7, drawn from spools (58 mounted on inclined pins, so as to producetension on the wires G7 when drawn from spools G8. The two wires 67,which are slightly twisted together before reaching a friction cylinder(Si),

'pass intothe frictioncylinder mounted on the beam 6, and after passing'through the friction cylinder the strand 43 with the wires 67 woundthcrcaround passes through a twister 70 corresponding to the twister 1,the strand 71 thus formed as a result of the seci'ond step, being woundon a spool 72.

. same number of twists as was given the strand 43 resulting from thefirst operation. From the point of engagement with the eye 66, however,down to the point where it enters the twisting mechanism 70, this yarnreceives approximately three twists to the left lper inch. Inasmuch asin the first operation the paper was twisted three times to the right,

and in the second operation the paper receives three twists to the left,the paper in the strand 71 resulting from the second operation will haveno twist. However, the wires or filaments pass from spools 68 to thepoint wherel the strand enters the twister and the'filaments or wires 67are then twisted three times to the left around the modified strand '43.There is obtained then at this stage, a strand or preliminary yarn 71 inwhich the paper has no twist and the wires have three twists to the leftper inch.

. In the third operation, the preliminaryI yarn 71 resulting from thesecon operation, is placed on spool 74 mounted in inclined position onthe upper beam of a frame, such as shown in Figure 1, and is leddownwardly therefrom toa twister 75 by which the yarn 7l is given threeadditional twists to the left, thus producing a yarn 76 having sixtwists of the wires or filaments to the left and three twists of thepaper to the left.

Although a certain number of twists is specified, the third operationmay consist in giving the yarn 72 any number of final twists, dependingupon the requisites of the trade and the kind of yarn desired. It shouldbe understood that the original twists may be either to the right or tothe left, and the reversal in such twists may be obtained in c the lateroperations. -The number of twists given to the yarn determines thestrength,`

homogeneity and tightness of the finished product, according tocommercial requirements, and is an important factor in determining thequality of fabric made from the yarn.

The wires 67 are preferably' of brass and it has been found that, whencombined directly with moist asbestos paper strips in forming yarn,there is considerable corrosion and deterioration of the wires which mayre suit in breakage thereof. Such deterioration may be due to somegalvanic or electrolytic action and may be avoided by coating thewires'with suitable material. A coating of paraffin wax has been foundto give very satisfactory results and as disclosed in this application,the wires are passed through a pig tail guide 77, under a roller 78,submerged to its axis in melted paraffin in a vessel or pot 78 and overa roller 79 which de termines the direction of ent-rance of the wires G7into the friction cylinder (Si). The paraffin is kept in meltedcondition by means of a steam pipe 8O in the pot 78.

In recapitulation, the invention may be stated to comprise, in general,the steps of making paper, having incorporated therein, binding'materialwhich is not substantially vweakened by moistening the asbestos strip,

and which may contain lubricating material, of moistening the asbestosstrip with water, or, if desired, a solution containing material whichwill keep the strip soft, flexible and vmoist; of forming a strand ofasbestos paper and cotton threads twist-ed in one direction; of addingone or more filamentary bodies or lwires to support the strand andwrapping them about the strand already formed by a twist in a directionopposite to`that`of the first, and sufficient to leave the stripsubstantially without twist; of giving the yarn a final tighter twist,tending to embed the wires inthe paper material at the surface of theyarn, the twists in different steps being the reverse of in differentdirections as hereinbefore specified; and` of making fabrics from saidyarn. By making the twist in the second operation that in the firstoperation and sufficient in extent to leave the paper stripsubstantially without twist, the tension on the paper strip is relieved,thus reducing the danger of rupturing the asbestos paper strip duringthe third step in which a tighter twist isgiven to the yarn or in thelater operations, such as weaving. It should be understood that theextent of the twists'in the ldifferent directions maybe varied and thatthe material and number of core filaments Y and binding filaments may bechanged with- ''o ut departing from the spirit of the mvenas by weaving,

ing the frictional tlon.

The invention also comprehends fabrics made from/the yarn in anysuitable manner,

braiding andknitting, and of such texture, strength, thickness and otherqualities, as to meet the requirements service for which they aredesigned. As illustrated in Figures 6 and 7, the fabric comprises warpthreads or yarns 8l and weft threads or yarns 82. Preferably, said warpand weft yarns are so interwoven that the vwearing surface is made upprincipally ofv Fabrics made from such-yarn warp yarns. have been 4foundto give particularly desirable results when used -for brake linings,clutch linings and the like. The rosin in the paper serves to givesuitable strength and friction qualities, and the graphite` in the paperhas been found to play a great part in giving to the fabric of thepresent invention, its features of superiority. the paper serves tolubricate the guides through which the material is drawn in the courseof yarn manufacture thereby renderdrag on the yarn uniform and impartingto the yarn a uniform strength and structure.

rEhe graphite acts as a lubricant to render the braking action of thebrake lining Amore smooth and to prevent sudden gripping, and due to itslubricating qualities,'t'ends to keep the surface of the brake bandsmooth and to prevent undue hardening of the bandy at the brakingsurface. It has also been found that the brake bands containinggraphite, substantially retain their effectiveness when wet and,therefore, are reliable in -wet weather. Another quality of graphitewhich of the The graphite inV renders it of particular value in brakelinings, is that of great resistance to heat. The brake liningcontaining graphite is therefore not affected, by ordinary changes intemperatureas to friction or other qualities. Inasmuch as graphite is avery good conductor of heat and therefore dissipates'heat rapidly, it isvery much more diflicult to heat up a lining containing graphite and,when heated. the lining cools very rapidly. Although such brake liningsare preferably of fabric made from asbestos yarn, theinvention is ofsuch breadth as to include friction fabrics containing asbestos materialand graphite, but formed without first manufacturing asbestos yarn. I

It should be understood that the apparatus herein disclosed is merelyillustrative of the invention, and that various. changes may be made inthe construction and arrangement of the parts without departing' fromthe spirit of the invention.

It should be understood that the term asbestos material, wherever itappears in the specification and claims, is intended to refer tomaterial having a substantial percentage of asbestos libres, such as togive more or less the characteristics of asbestos as far as working andhandling are concerned, and the term asbestos material, where used inthe specilication and claims, shall be considered as thus defined.

I desire toclaim as my invention l. A method of making asbestos materialadapted for use in yarn manufacture and other uses which comprisesincorporating inasbestos containing pulp a binding agent, and a materialadapted to soften said asbestos containing pulp, and thereafter formingthe desired product therefrom.

2. A method of making 4asbestos paper for use in the manufacture ofyarn, which consists in forming pulp of asbestos material, disseminatinga rosin material and graphite therethrough, and binding such materialwith the rosin and graphite distributed therethrough into paper.

3. An asbestos product having a binder and a material to prevent unduehardening of the binder.

Il. An asbestos product including a binder containing resin," andmaterial to prevent undue hardening of the binder.

5. An asbestos product including a binder l also a lubricating materialtherein to insure y 'smooth frictional action; andl a material forpreventing undue hardening of the binding material.

8. An asbestos product for friction purposes having disseminatedtherethrough friction binding material including resin, and havingtherein lubricating material to insure smooth frictional action andmaterial for preventing undue hardening of the binding material.

9. An Aasbestos product for friction purposes having disseminatedtherethrough friction binding material, lubricating material includinggraphite to insure smooth frictional action, and material for preventingundue hardening of the binding material.

l0. An asbestos product for friction purposes having disseminatedtherethrough friction binding material, lubricating material to insuresmooth frictional action, and glycerine for preventing undue hardeningof the binding material. J y

11. A method of making an asbestos product adapted for various uses suchas for sheets, fabrics, paper, yarn, for friction elements as in brakelinings, and various other uses which comprises incorporating in anasbestos containing pulp a binding material adapted to increase theadhesion of the finished product and to impart sufficient strengththereto to render it suitable for manipulation to Withstand the stressesarising in the various operations of manufacture, adding a material forpreventing undue hardening of the binding material, and forming thedesired product from theoresulting pulp material.

l2. A methodof making an asbestos product adapted for various uses,which comprises l incorporating in an asbestos containing pulp materiala binder adapted to increase the coherence of the said asbestosmaterial, and incorporating therewith a lubricating material, the saidmaterials being incorporated in proportions such that the resultingproduct will have suiiicient adhesion or coherence in the wettedcondition to permit being mechanically Worked, and thereafter formingthe desired product therefrom.

13. A method of making an asbestos product for use in manufacturingasbestos yarn and other uses which comprises forming a pulp of asbestosmaterial, treating a resinous material in such a manner chemically so asto render it soluble in water, disseminating the treated resinousmaterial throughout the pulp, adding a material to form a substantiallyinsoluble compound therefrom, and forming the desired product witlrthesaid compound distributed therethrough.

14. A method of making an asbestos` produotforluse in manufacturingasbestos yarn and other uses which comprises forming a pulp of asbestosmaterial, treating a resinous material in such a manner chemically as torender it soluble in water, forming a Water solution thereof anddisseminating the treated resinous material throughout the pulp andthereafter adding a material thereto to form an insoluble resinate inthe pulp to impart the desired strength to the product in the wettedcondition so as to permit being mechanicallyI worked, and thereafterforming the desired product therefrom.

In testimoiq7 whereof, I aix my signature.

WILLIAM NANFELDT.

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CERTIFICATE or CORRECTION.

Patent No. 1,758,055. Granted May1 13, 1930, to

WILLIAM NANFELDT..

It is hereby certified thatverror appears in the printed specificationof the above numbered patent requiring correction lsf? follows: Page 3,iine 4 for "1,585,628" read 1,585,626; and that the said Letters Patent`should he read with this correction therein that the same may.contormto the record of the case in the Patent Office.

Signed and sealed this 5th day of August, A. D. 1930.

Wm. A. Kinnan,

(Seai') Acting -Commissioner of Patents.

